1. Field of the Invention
The present invention relates to lumbar supports for seats, and more particularly to seats having a trim wire in a foam support.
2. Related Art
Many different types of lumbar supports have been installed into seating systems using a variety of mounting and fastening devices. For example, U.S. Pat. No. 5,022,709 teaches various combinations of hinges, tabs, pins and shims to connect a back support to the seat frame. In another example, U.S. Pat. No. 6,918,884 teaches various combinations of guide rods, back plates, and brackets to connect a lumbar support to the seat frame. In yet another example, Published Patent Application US2005/0179506 teaches the use of side wires or rods that form a portion of the seat back's wire basket and extend out to and connect with the seat frame. According to the description of this earlier invention, the foam cushion has wires that are connected to these frame attachment wires, and as the ergonomic support is actuated within the frame, the foam cushion is driven through this connection. However, according to the teaching of this publication, the bolsters and any lumbar support remain are connected to and supported by the seat frame rather than being supported by the trim wires. Finally, U.S. Pat. No. 7,011,369 teaches a lumbar support that is integral with a trim attachment array. However, as particularly taught by the '369 patent, the integral with a trim attachment array “is adapted to replace the standard trim wires which are molded into the seat back and cushion foam of a standard, state-of-the-art vehicle seat.”
In each of these prior art seating systems, the lumbar device is typically attached to the seat frame in a vertical or horizontal manner which requires custom packaging and new tooling and design for the frame attachment. Additionally, plastic components are also typically required to eliminate the BSR issues for the seats. For example, guide wires traditionally support a vertical lumbar within the seat frame, and wing wires traditionally support a horizontal lumbar within the seat frame. Accordingly, the frame requires holes, lance tabs, or other brackets or mounting structures to support the lumbars. Therefore, the traditional designs requires a custom fit for each seat frame because wing wires must be configured differently for each particular frame due to varying width, tapering, foam interference and/or reclining clearance issues.
Modular seat assembly techniques require components to be designed for ease and speed of assembly. Modular lumbar supports often include vertical extensions. In both assembly and finished use, the extra leverage such extensions place on anchors can cause undesirable wear and binding. Accordingly, along with the need for strong, economical, compact components in seat design, there is a continuing need in seat assembly procedures to increase the economy, speed and efficiency of component assembly and shipping. Furthermore, as described in U.S. Pat. No. 5,553,919, US Pub. No. 2004/0108760, and U.S. Ser. No. 11/295,425, there is a benefit for providing spinal relief when supporting the spine or for using a shaped pad to provide comfort. It is preferable to apply lumbar supporting pressure bilaterally adjacent to the spinal column, while maintaining a vertical recess or channel to accommodate the vertebrae, because the bony vertebrae of the spine may become uncomfortable if direct pressure is applied to them by a lumbar support pressure surface.
Therefore, there is a need in the art for an improved lumbar support that can be easily fit into any seat back using a foam pad with a trim wire and that reduces the space required for installation of the lumbar support. Further, there is a need in the art for an improved lumbar support that reduces the components required to fit the lumbar into the seat frame and also minimizes noise, shake and rattle (generally referred to as BSR). Even though some prior art references have suggested connecting back support wires to a wire in the foam cushion of the seat or using an integral trim attachment array for supporting a lumbar, none of these references teach or suggest using a standard trim wire design to support a lumbar within the seat's foam pad. Accordingly, there remains a need for such a system which can be adapted to any seat that already uses a trim wire that is at least partially embedded in foam padding so that no changes are required to the design of the seat other than increasing the strength of the trim wire to support the lumbar. Additionally, there continues to be a need for strong, economical, compact components that further increase the economy, speed and efficiency of component assembly and shipping. Finally, all of these structural and assembly criteria should be accomplished with the goal of maintaining the comfort of the seat.